I've taken GMAT twice - once at the Dwarka Centre and once at the Yusuf Sarai Center New Delhi. Well, I must say they are exact opposite of each other.

In terms of staff, Pearson Center has really cooperative staff who actually listen to your whims and fantasies.
They have their own washroom unlike the Dwarka EduPro centre where I had to go from 4th to 2nd floor and into a ladies toilet that was actually a flooded common toilet... Yukkk..

Also, Pearson center's test room is sound proof and quite comfy. The PCs are bigger, charis are good and most importantly, the separators from fellow test takers is really good. At EduPro it was like a primitive cyber cafe with not more than a foot high separators... no use.

I was an outstation candidate so cant comment on parking space but the nearby area is good with great connectivity by metro trains.

I would really suggest that whether u have to postpond/prepond your appointment, dont book EduPro centre. Go for Pearson center.